MGM Springfield on Friday was named the state's first official casino operator, capping a more than two-year process that saw four other rival plans in western Massachusetts fall by the wayside.

The Massachusetts Gaming Commission voted unanimously at the MassMutual Center to approve a deal granting MGM the casino license, pending the outcome of efforts to repeal the state's casino law.

Commission Chairman Stephen Crosby said the $800 million proposal for a casino, hotel, and entertainment and shopping complex in downtown Springfield captures the "spirit" and "aspirations" that state leaders envisioned when they opened the door for resort-style casino gambling in Massachusetts in 2011.

MGM's casino license is one of three authorized under the state's casino law. The two others are in the Boston area and the Fall River/New Bedford area.

The gaming commission has already awarded the state's lone slot parlor license to Penn National Gaming for its project at the Plainridge harness racing track in Plainville.

Springfield Mayor Domenic Sarno said the vote represents a "pivotal" moment in the economically struggling city's history. The former manufacturing center is the state's third largest city and has one of its highest unemployment rates.

"People are hungry to work," Sarno said.

MGM Resorts International CEO James Murren said the approval process was one of the most rigorous that the Las Vegas-based gambling giant, which owns the Mirage, Bellagio and other major casinos, has gone through.

The casino was the only project to make the commission's final review. Plans by Penn National Gaming and Ameristar Casinos never went before Springfield voters, while plans by Mohegan Sun in Palmer and Hard Rock International in West Springfield were defeated in local referendums.

But as its likely approval approached, MGM balked at the prospect of paying millions of dollars of state fees and other payments that would it owe if it was awarded the license.

Under the terms approved Friday, the state would grant MGM the western region casino license but not require it to pay the $85 million licensing fee that would be due under law.

MGM will pay the fee only after the state Supreme Judicial Court decides whether a referendum to repeal the state's casino law is allowed on the November ballot. That decision is expected before July 9.

If the court blocks the referendum, MGM would pay the fee in about eight business days. If the court permits the question, MGM pays only if the referendum is defeated.